How to Calculate Heart Rate Percentage

Heart Rate Percentage Calculator

Calculation Results

Estimated Max Heart Rate (MHR): BPM

Standard Percentage: % of Max

Karvonen Intensity (HRR): %

function calculateHRPercentage() { var age = parseFloat(document.getElementById('userAge').value); var currentHR = parseFloat(document.getElementById('currentHR').value); var restingHR = parseFloat(document.getElementById('restingHR').value); if (!age || !currentHR || age <= 0 || currentHR 0) { hrrPercentage = ((currentHR – restingHR) / hrr) * 100; } document.getElementById('maxHRVal').innerText = maxHR; document.getElementById('simplePercVal').innerText = simplePercentage.toFixed(1); document.getElementById('hrrPercVal').innerText = hrrPercentage.toFixed(1); var indicator = document.getElementById('zoneIndicator'); var perc = simplePercentage; if (perc = 50 && perc = 60 && perc = 70 && perc = 80 && perc < 90) { indicator.innerText = "Zone 4: Hard / Anaerobic (80-90%)"; indicator.style.backgroundColor = "#fadbd8"; indicator.style.color = "#c0392b"; } else { indicator.innerText = "Zone 5: Maximum Performance (90-100%)"; indicator.style.backgroundColor = "#e74c3c"; indicator.style.color = "#ffffff"; } document.getElementById('hr-results').style.display = 'block'; }

How to Calculate Heart Rate Percentage: A Complete Guide

Understanding your heart rate percentage is one of the most effective ways to gauge your exercise intensity. Whether you are aiming for weight loss, improved cardiovascular endurance, or peak athletic performance, knowing which "zone" you are training in is vital for success.

1. The Basic Formula (MHR Method)

The most common way to calculate your heart rate percentage is based on your Maximum Heart Rate (MHR). The standard formula used by many fitness professionals is:

• Step 1: 220 – Your Age = Max Heart Rate
• Step 2: (Current Heart Rate / Max Heart Rate) x 100 = HR Percentage

Example: If you are 30 years old, your Max HR is 190 BPM. If your current heart rate is 142 BPM, you are working at roughly 75% of your maximum heart rate.

2. The Karvonen Formula (Heart Rate Reserve)

Advanced athletes often use the Karvonen Formula, which accounts for your Resting Heart Rate (RHR). This method is considered more accurate because it reflects your actual fitness level. It calculates the Heart Rate Reserve (HRR), which is the difference between your Max HR and your Resting HR.

Karvonen Calculation: Target HR = ((Max HR − Resting HR) × %Intensity) + Resting HR.

Understanding Training Zones

Zone	% of Max HR	Benefit
Zone 1	50% – 60%	Recovery and basic health improvement.
Zone 2	60% – 70%	Fat burning and aerobic endurance.
Zone 3	70% – 80%	Aerobic capacity and cardiovascular strength.
Zone 4	80% – 90%	Anaerobic capacity and speed endurance.
Zone 5	90% – 100%	Maximum performance and high-speed power.

Why Calculate Heart Rate Percentage?

By monitoring your heart rate percentage, you ensure that you are not overtraining (which can lead to injury) or undertraining (which can lead to a plateau). For instance, if your goal is weight loss, staying consistently in Zone 2 is often recommended as the body primarily uses stored fat for fuel at this intensity. Conversely, for VO2 Max improvement, you need to spend time in Zone 4 or 5.

Pro Tip: Always measure your resting heart rate in the morning, immediately after waking up and before consuming caffeine, to get the most accurate baseline for your calculations.